Inorganic Chemistry Commons^™

Synthesis And Characterization Of A New Cyano-Substituted Tris(Pyrazolyl)Borate And Its Thallium(I) Complex, Bozumeh Som

Electronic Theses and Dissertations

A new cyanoscorpionate - tris(4-cyano-3,5-diphenylpyrazolyl)borate (Tp^Ph2,4CN) has been synthesized and characterized. The thallium complex of this ligand TlTp^Ph2,4CN has also been prepared and characterized by FT-IR, ¹H NMR, and single-crystal X-ray-diffraction. The complex TlTp^Ph2,4CN crystalized in the monoclinic space group C2/c with unit cell a = 14.6697(10) Å, b = 13.9493(10) Å, c = 19.3347(12) Å, and b= 91.761(2)°. Structural comparison of TlTp^Ph2,4CN with analogous complexes demonstrated the effects of both steric and electron-withdrawing substituents on coordination geometry and the electronic properties of the metal ion. There were short contacts between the cyano groups …

New Bis(Imino)Pyridine Complexes Of Iron(Ii) And Iron(Iii), And Their Catalytic­ Activity In The Mukaiyama Aldol Reaction, Pushkar Shejwalkar, Nigam Rath, Eike Bauer

Chemistry & Biochemistry Faculty Works

New iron(II) and iron(III) complexes bearing bis(imino)pyridine ligands were synthesized and successfully applied to the Mukaiyama aldol reaction. The two complexes [FeCl2 L] (L = bis(imino)pyridine ligand, 55% isolated yield) and [LFe(μCl)3FeCl3] (76%) were obtained employing FeCl2 and FeCl3 iron sources, respectively, and characterized by elemental analyses, mass spectrometry, IR spectroscopy and, one example, by X-ray diffraction. The two new iron complexes were subsequently employed as catalysts in the Mukaiyama aldol reaction after abstraction of two chlorides by AgSbF6 to obtain the aldol products in 43% to virtually quantitative yield (CH2Cl2 solvent, room temperature, 3.5 to 16 h reaction time). …

Utilization Of Biomass Derived Furans In Value-Added Organics And Heterogeneous Oxorhenium Catalysts For Deoxydehydration Of Diols, Benjamin L. Wegenhart

Open Access Dissertations

As fossil fuels are depleted, there is a growing focus on renewable chemicals based on biomass materials, including both fuels and chemical feedstocks. Current methods for biomass utilization include biological conversion to produce ethanol and various thermochemical routes (gasification, pyrolysis, liquefaction, hydrothermal treatment, etc.). Furfural is one particular chemical that can be obtained from lignocellulosic biomass in good yields through the dehydration of sugar residues. It can be used as a feedstock for chemicals such as furan and THF, or as a platform molecule for making liquid fuels. The objective of this research is to investigate new pathways for the …

Spectroscopic Characterization Of The Water-Oxidation Intermediates In The Ru-Based Catalysts For Artificial Photosynthesis, Dooshaye Moonshiram

Open Access Dissertations

Utilization of sunlight requires solar capture, light-to-energy conversion and storage. One effective way to store energy is to convert it into chemical energy by fuel-forming reactions, such as water splitting into hydrogen and oxygen. Ruthenium complexes are among few molecular-defined catalysts capable of water splitting. Insight into the mechanism of their action will help to design future robust and economically feasible catalysts for light-to-energy conversion. Mechanistic insights about the design of such catalysts can be acquired through spectroscopic analysis of short-lived intermediates of catalytic water oxidation. Development of time-resolved approaches through stopped flow UV-Vis Spectroscopy to follow the catalysis of …

Spectroscopic And Kinetic Study Of Copper-Exchanged Zeolites For The Selective Catalytic Reduction Of Nox With Ammonia, Shane Adam Bates

Open Access Dissertations

The recent application of metal-exchanged, small-pore zeolites for use in the selective catalytic reduction (SCR) of NO_x with ammonia NH₃ for automotive deNO_x applications has been a great stride in achieving emission standard goals. Copper-exchanged SSZ-13 (Cu-SSZ-13), the small-pore zeolite in this study, has been shown to be very hydrothermally stable and active under conditions presented in the exhaust of the lean-burn diesel engine. In this work, detailed studies were performed to identify many aspects of the active site(s) in Cu-SSZ-13 in order to learn about the standard SCR mechanism.

A series of seven Cu-SSZ-13 samples were …

Conversion Of Iodide To Hypoiodous Acid And Iodine In Aqueous Microdroplets Exposed To Ozone, Elizabeth A. Pillar, Marcelo I. Guzman, Jose M. Rodriguez

Chemistry Faculty Publications

Halides are incorporated into aerosol sea spray, where they start the catalytic destruction of ozone (O₃) over the oceans and affect the global troposphere. Two intriguing environmental problems undergoing continuous research are (1) to understand how reactive gas phase molecular halogens are directly produced from inorganic halides exposed to O₃ and (2) to constrain the environmental factors that control this interfacial process. This paper presents a laboratory study of the reaction of O₃ at variable iodide (I^–) concentration (0.010–100 μM) for solutions aerosolized at 25 °C, which reveal remarkable differences in the reaction intermediates …

Structure, Theoretical Studies And Coupling Reactions Of Some New Cyclic Boronic Esters, Andrew Kuttler, Sravanthi Durganala, Albert Fratini, Alexander Morgan, Vladimir Benin

Chemistry Faculty Publications

The present report describes the X-ray structural and theoretical studies of some new pinacolboronate esters, and it also outlines the use of the target structures in Suzuki coupling reactions to produce new aromatic or heteroaromatic esters and amides. X-ray structural analysis of the studied compounds revealed that the pinacolborane ring's position with respect to the benzene ring varies, depending on the particular environment. An ortho-positioned carboxylic ester (methyl ester) causes a nearly perpendicular orientation of the pinacolborane unit with respect to the benzene ring, whereas an ortho-positioned amide (N,N-dimethylamide) causes the pinacolborane unit to orient itself nearly coplanar. A plausible …

Transition Metals As Tools To Probe The Electronic Properties Of Porphyrinoids, Jillian Worlinsky

Chemistry Education Materials

This thesis describes in a number of separate chapters a range of studies that measure the variation of specific physical properties with structural modification of the macrocycles, with a particular focus also on using their coordinated metals as probes. Specifically, the transition metal ions are used as tools for interrogation of the electronic properties of porphyrins and pyrrole-modified porphyrins. With the aim of better understanding the electronic and structural factors that govern the optical responses, axial binding strengths, fragmentation patterns and carbonyl stretching frequencies of meso-tetraarylporphyrins, a rational design of pyrrole-modified metalloporphyrins with designed optical properties is derived.

Io3- And I- Sorption From Groundwater By Layered Double Hydroxides, Abbey Rickelmann, Emily Campbell, Natasha Pence, Tatiana Levitskaia, Sayandev Chatterjee, Frances Smith

STAR Program Research Presentations

Several subsurface water plumes are found at the Hanford U.S. DOE site. These plumes contain many different types of hazardous components including radioactive iodate (IO₃^-) and iodide (I^-), which may have deleterious health effects. To selectively uptake IO₃^- and I^-, inorganic layered double hydroxide (LDH) compounds were synthesized and tested. LDHs are mixed transition metal hydroxides that contain positively charged layers that undergo anion exchange. When LDHs are submerged in the plume water, they can selectively uptake IO₃^- and I^- and remove them from the plume. Raman spectroscopy …

Analysis Of Kyrock For Leaching Of Impurities In Synthetic Rainwater, Santhosh Kumar Kasulavada

Masters Theses & Specialist Projects

Kyrock is a coarse grained sandstone with a complex mixture of organic and inorganic compounds. Mining of Kyrock is for use in road construction and roofing. Kyrock samples were analyzed using scanning electron microscopy to obtain elemental analysis. High levels of carbon indicate the presence of organic compounds. Analysis of an acid digestion of the samples using inductively coupled plasma spectroscopy showed inorganic compounds such as titanium oxide, vanadium oxide along with traces of arsenic. Elemental analysis of samples indicates a percent of carbon, and sulfur with no notable traces of nitrogen. Pyrolysis of the samples was done using gas …

Selective Catalytic Oxidation Of Organic Sulfides By Iron (Iii) Porphryin Catalysts And Generation Of Iron (Iv)-Oxo Prophyrin Radical Cations, Nawras A. Asiri

Masters Theses & Specialist Projects

Macrocyclic ligand-complexed transition metal-oxo intermediates are the active oxidizing species in a variety of important biological and catalytic oxidation reactions. Many transition metal catalysts have been designed to mimic the predominant oxidation catalysts in nature, namely the cytochrome P450 enzymes. Iron porphyrin complexes have been the center of research as catalysts. In this study 5,10,15,20- tetramesitylporphyrin (H₂TMP) and its corresponding iron complexes Fe^III(X)TMP (X= Cl, ClO₄, ClO₃, NO₃, NO₂, and BrO₃) have been successfully synthesized and fully characterized by UV-vis and NMR spectroscopies. For the catalytic …

Synthesis And Computational Studies Of A New Class Of Lanthanide Niobate Cluster : [Ln4(H2O)8(So4)5(Nbo3)2]+3h2O; Ln= Dy, Tb, Brady D. Garabato

Masters Theses & Specialist Projects

Polyoxoniobates (PONbs) are a small family of highly electron-rich clusters. The development of new solids composed of these clusters have applications in green energy and electronics. However, the high charge environment of PONbs typically requires alkaline synthetic conditions that are unsuitable for introducing other metals and organic molecules, making synthesis of new systems difficult. To date, very few transition metals and organic ligands have been incorporated into these PONb solids, and lanthanide metal inclusion, which generally improves photoconductivity due to longlived f-orbital excitations, has not yet been fully realized. Here, the synthesis of a new class of lanthanide niobate cluster …

Ionic Conductivity In Non-Ionic Compounds, Usha Kranthi Avala

Masters Theses & Specialist Projects

The main objective of this work is to investigate the ionic conductivity of the drugs under certain conditions and also to compare the ionic conductivities of drugs determined by single surface sensors and parallel plate sensors. The ionic conductivity of various materials at their pre-melt and melt states are studied in order to further study a recently discovered phenomenon. Polar solids like Lidocaine, Ketoconazole, Procainamide and Nifedipine were examined in this study. Experimental studies show an increase in ionic conductivity in both pre-melt (20 -30 °C below melting temperature) and melt transition regions. Results of ionic conductivity of both parallel …

X-Ray Crystal Structures Of: [Rh2(N-{2,4,6-Ch3}C6h2)Coch3)4]•2ncc6h4 And Ba1.5[Fe(C10h13n2o7)][Co(Cn)6]•9h2o; Two Crystallographic Challenges, Kenneth K. Kpogo

Electronic Theses and Dissertations

The novel compound, [Rh₂(N-{2,4,6-CH₃}C₆H₂)COCH₃)₄] was synthesized. Crystal structures of [Rh₂(N-{2,4,6-CH₃}C₆H₂)COCH₃)₄]·2NCC₆H₅ and Ba_1.5[Fe(C₁₀H₁₃N₂O₇)][Co(CN)₆]·9H₂O were determined employing a Rigaku Mercury375R/M CCD (XtaLAB mini) diffractometer with graphite monochromated Mo-Kα radiation. For [Rh₂(N-{2,4,6-CH₃}C₆H₂)COCH₃)₄]·2NCC₆H₅, the space group was P-421c(#114) with unit cell dimensions: a =11.0169(14)Å, c =21.499(3)Å, V …

Characterization By Nmr Of Reactants And Products Of Hydrofluoroether Isomers, Cf3(Cf2)3och3 And (Cf3)2c(F)Cf2och3, Reacting With Isopropyl Alcohol, Howard Knachel, Vladimir Benin, William E. Moddeman, Janine C. Birkbeck, Thomas A. Kestner, Tayna L. Young

Chemistry Faculty Publications

The 3M Company product Novec™ 71IPA DL, a mixture of methoxyperfluorobutane, methoxyperfluoroisobutane and 4.5 wt.% isopropyl alcohol, has been found to be very stable at ambient temperature, producing fluoride at the rate of ~1 ppm/year. Our earlier kinetic and theoretical studies have identified the reaction mechanism. This paper identifies the ¹H and ¹⁹F NMR chemical shifts, multiplicities, and coupling constants of reactants and the major products that result from aging the mixture in sealed Pyrex NMR tubes for periods up to 1.8 years at temperatures from 26 °C to 102 °C. Chemical shifts and coupling constants of fluorine …

A, Catalysis Of Co-Prox By Water-Soluble Rhodium Fluorinated Porphyrins. B, Studies Toward Fluorination Of Electron Rich Aromatics By Nucleophilic Fluoride, Shri Harsha Uppaluri

Department of Chemistry: Dissertations, Theses, and Student Research

The rhodium(III) derivative of a water soluble, heavily fluorinated porphyrin is shown to catalyze the low temperature, low pressure selective oxidation of carbon monoxide in hydrogen gas streams for use in fuel cell applications. The catalytic activity is a direct result of the removal of electron density from the metal center. Selectivity for CO oxidation is a direct consequence of fluorination of the porphyrin periphery, since these substituents enhance the rate of the reaction and prevent the formation of Rh(II)-Rh(II) dimmers. Significantly, the dramatic increase in rhodium hydride acidity caused by fluorination precludes hydrogen activation and generation, thereby permitting preferential …

Surface Tethered Pamam Dendrimers On Controlled Pore Glass As Color Release Sensors For Phosphates, Chang Liu

Master's Theses

Poly(amidoamine) dendrimer (PAMAM) are highly branched macromolecules with reactive amine groups in their interior and exterior. PAMAM dendrimers were attached to controlled pore glass (CPG) surfaces in order to create new functionalized surfaces and used as platforms for UV-vis and fluorescent sensing of phosphate substrates via indicator displacement assays (IDA).

CPG surfaces were first modified with different sized PAMAM dendrimers (generation 3.0, 4.0, and 5.0), then reacted with two strong metal-chelators: aminofunctionalized terpyridine (synthesized from 2,2’:6’,2’’-terpyridine) and Nα-Nα-bis(carboxymethyl)-L-lysine (Lys-NTA). First of all, Cu(II) metal ion binding capacities were measured on the surfaces. Second, two terminal group density tests, amine assay …

Nanomaterials For Biological Applications: Drug Delivery And Bio-Sensing, Hui Ma

LSU New Orleans Theses and Dissertations

The idea of utilizing nanomaterials in bio-related applications has been extensively practiced during the recent decades. Magnetic nanoparticles (MPs), especially superparamagnetic iron oxide nanoparticles have been demonstrated as promising candidates for biomedicine. A protective coating process with biocompatible materials is commonly performed on MPs to further enhance their colloidal and chemical stability in the physiological environment. Mesoporous hollow silica is another class of important nanomaterials that are extensively studied in drug delivery area for their ability to carry significant amount of guest molecules and release in a controlled manner.

In this study, different synthetic approaches that are able to produce …

The Investigation Of Protonation Of [Mo2(Nto)2(S2p(Oet)2)2(So)(Sbn)(O2cme)]., Adria Schwarber

College of Arts & Sciences Senior Theses

No abstract provided.

Interaction Between Lubricants Containing Phosphate Ester Additives And Stainless Steels, David W. Johnson, Matthew Bachus, John E. Hils

Chemistry Faculty Publications

One way to improve fuel efficiency in today’s jet aircraft engines is to create an environment for higher operating temperatures and speeds. New and improved lubricants and bearing materials must be developed to remain stable in these elevated operating temperatures. Three lubricants, with varying amounts of tricresyl phosphate added as an anti-wear/extreme pressure additive were tested on two different stainless steels at varying temperatures ranging from 300 °C to 350 °C in vacuum. Significant decomposition of the lubricant base-stocks and the phosphate ester additive did occur in most of the trials resulting in the formation of carboxylic acids and phenols. …